Electrical means for controlling lifts and the like



Nov. 20, 1928. I 1,692,542

A. BOSSELUT ELECTRICAL MEANS FOR CONTROLLING LIFTS AND THE LIKE Filed Jan. 19, 1926 mmqz ATTO Mm PatentedQNov. 20, 1 9 28.

PATENT jorFics. j

an'roiivn BossELUT; or PARIS; FRANCE. I

ELECTRICAL inn-Ans FOR 'ooNrnoLLnve iars Nnf'rHE LIK Applicatlon'filed January 19, 1926, Serial No. es 274, and in France members, 1925.

known that one of the problems met with in lifts and the like is that stopping the cage at a landing with prec sion.

This is the case especially for lifts in which. the arrest is caused by breaking the feed cir-,

cuit of the driving motor, and the circuit bringing the cage brake into action; this breaking of the circuit usually takes place ataconstant distancefroma'landing- Thishas ingeneral the effect with the same ascent speed of the cage to produce difference it of level between the floor offlthe cage and the landing which :will varyin accordance with the load. If it were possible at each journey to break the circuit at a point which varies asa function of the load on the cage it will easily be seen that there would cease to be any substantial difference in level between the floor of the cage and a landing. This invention has for its ob ect to solve this latter problem. 1

Accordingto this invention the point where the circuit is broken for the arrest of the cage is automatically varied with respect to a landing as a function of the loadinthe cage by the aid ofa' wattage relay or other similar apparatus whiclicauses a HiOYillDlGHleIIlbGl tobe' given an angular displacement strictly proportional to the energy absorbed bythe drive of the cage in normal action. a For example,.the time required for said movable member to return tozero (a period which is also proportional to the energyabsorbcd and therefore to the load on the cage) may be utilized to break the hoisting motor circuit for the cage at the required moment with respect to a landing depending on the speed of, the lift, while the ordinary floor contact .of the cage is always broken in the usual manner when the cage is at a constant distance" (suitably predetermined once for all) from the said landing. I

The cage will thus always attain its precise level at the landing whatever the load there- As will be seen this arrangcnu-int is entirely electricaland is very sensitive.

The invention is illustrated diagraminati motor; C the landing at which the cage stops.

a is the corresponding landing contact acwhen the shaft 8 is in zero or neutral tuated in known manner by the movement of the cage through a cum 6 on the cage.

In carrying out'n'iy invention I provide means responsive to the quantity of energy be ing consumed .by the hoisting motor B for v timing the opening of the hoisting inotorcircuit. This means comprises a wattage relay D for controlling the contact 10. The wattage relayl) is of a known type and comprises the.

member 7 movable angularly about its axis and constructed as a part of a'usualelect-ric flow meter. In the embodiment shown this resulting first, from a series Winding 1 placed v "as indicated at 3 on the main current feeding the motor B and from a parallel winding 2 connected as a shunt around the motor B and controlled by the relay 15.

A spring R resiliently opposes the rotative movement of the shaft 8 and the parts carried thereby with the result that the greater the power consumed by the motor B the i greater the angular movement of the disk 8 and shaft 8, the spring R'servingto return the parts to their zero position. The damper disk 8 is braked by the magnet 11 so as to in surean absolutely constant speed while the shaft and elements carried thereby are being returned to zero; a

A supplementary winding 5 superposed on the winding 1: and regulated by a rheost'at 6 adds its effect to the winding 1 in order to render these effects always positive e., in the same directionas the rotation oft-he disk 8 The winding 5 is such that the rotation of the movable member 7 is positive for the most feeble load on the cage.

The energization of the winding 2 of the wattage relay D'being connected to the contacts 17 and 18 the movable member 7 will start backto zero at the instant the circuit is of a cam Z) and switch (1. =12 is the contact-relay of motor B; the energization circuit of this relay may pass:

1. Either through conductors 1314 the circuitbeing established when a relay 15, placed under the control of the usual drive circuit 16+16 of the cage and comprising contact a, is energized. The energized relay broken by the relay 15 through the operation through the circuit 2222 which comprises.

the contact 10.

The operation of the device will be readily understood from the above description. .Vhen the cage is moved upwardly, for example and the usual controls (not shown) have been actuated for stopping the cage at the floor C, the cage, as it approaches the landing C, will mechanics ly open'the switch a, by means of cam 5, thus de-energizing the relay 15 and opening oneof the parallel circuits to the relay 19.. De-energizing the relay 15 also opens contacts 1?, 18 thus opening the circuit through the coil 2 and (ls-energizing the wattage relay. The rotatable elements of this relay then move toward zero at a uniform speed and in .a time dependent upon the energy being consumed by the hoisting motor B, that is, if a large wattage is being consumed by the motor B then the disk 8 will have been turned to an extreme angular position and a longer time will be required iefore the arm 9 opens the contact 10 in the zero position of the shaft 8 It the motor B is operating under a light load the shaft 8 will have been turned to a lesser degree and the arm 9 will open the contact 10 shortly after the relay is tie-energized. It is obvious that the motor B will be consuming a large amount of energy when the cage A is heavily loaded and is moving correspondingly slowly. It will thus be seen that the hoisting motor circuitis opened through the wattage relay D and con trol relay 12 a longer period after the opening of switch a when the cage A is moving slowly with the heavy load than where it is moving more rapidly with the lighter load.

This system can be used on the continuous current as on the alternating current.

lVhat I claim is 1. In an electrically controlled lift the combination with a cage, of a limit switch associated with the cage, a second switch whose operation effects the arrest of the cage and means associated with the limit switch for operating the said second switch after a lag proportional to the load on the cage.

In an electricallyoperated liftthe combination with a cage, of a limit switch associated with the cage, a second switch in the motor circuit and means associated with the limit switch for operating the second said switch after a lag proportional to the load on the cage.

3. In an electrically controlled lift, the combination with a cage, of a limit switch associated with the cage, a movable member, means associated with the limit switch for giving said member an angular displacement proportional to the energy absorbed for drivmg the cage in normal action and means whereby die .1 urn of the said movable member to its initial position effects the arrest of the cage.

at. In an eectrically controlled liftthe combination with a cage, an electric motor drivthc cag a limit switch associated with the cage, a'wattage relay associated with said motor and with said switch. a movable member displaced when said relay is energized and means for breaking the circuit of the said motor on the return of said memberto its initial position.

5. In electrically controlled lift the com bination with a cage, an electric motor driving the cage, a limit switch associated with the cage, a wattage relay associated with said motor and with said switch, adjustable means to take into account the usual balance of the lift, a mm'ahle member displaced when said relay is energized and means for breakingt-he circuit of the said motor on the return of said member to its initial position.

6. In an electrically controlled lift, the combination with a cage, an electric motor driving the cage, a limit switch associated with the cage, a wattage relay associated with said motor and vith said switch, a winding connected to said relay, a rheostat for adjusting said winding a movable member displaced when said relay is energized and means for *iiecting the arrest of the cage onthe return of said member to its initial position.

7 In an electrically controlled lift the combination with a cage,a limit switch associated with the cage, a movable member, means for giving an angular displacement thereto in proportion to the energy absorbed on driving the cage and means whereby said member ceases to be driven and is allowed to return on the opening of the limit switch and means for breaking an electric circuit on the return of the movable member to its initial position.

In testimony that I claim the foregoing as my invention, I have signed my name this 31st day of December. 1925.

ANTOINE BOSSELUT. 

